Minimally Invasive Surgery vs Conventional Exposure Using the Miller-Galante Unicompartmental Knee Arthroplasty : A Randomized Radiostereometric Study

Forty-one patients were randomized to a cemented Miller-Galante unicompartmental (Zimmer, Warsaw, Ind) knee arthroplasty inserted with either minimally invasive surgery or with a standard exposure. Clinical data and conventional radiographs were recorded and patients were followed with radiostereometric analysis to measure migration rate of the tibial component. The rehabilitation of patients operated through a small incision was faster, and there was a significant difference in days of hospitalization (P = .03). No statistical significant difference was found between the 2 groups regarding clinical or radiographic data. The Hospital for Special Surgery score was 96 and 92, respectively, for the minimally invasive surgery and conventional group at 2 years. The limb alignment was equal in both groups with a mean femorotibial axis of 182° after surgery. The rate of migration for tibial components was very small, with a maximal total point motion of 0.8 mm for both groups after 2 years follow-up.